Augmented reality systems that overlay virtual content onto the real world are becoming increasingly popular. A user looking through their phone's camera might see a monster, a baseball player, or a movie character overlaid onto the background of real-world objects and geographic features in the camera's range. Augmented reality system may also be used for purposes other than recreation—travelers may use them for navigation, governments may use them for military training simulations, doctors may use them to practice surgery, and engineers may use them as visualization aids.
In any use of an augmented reality system, making the experience as seamless as possible may be critical. Regrettably, a variety of factors may disrupt augmented-reality immersion, and one of the most significant disruptions to having an immersive experience may be a phenomenon known as “vergence-accommodation conflict.” Traditional augmented-reality displays may attempt to create the illusion that a virtual object is set at a distance in the real-world environment by displaying virtual images to the left eye and to the right eye with a relative offset, such that a user's eyes converge on the desired real-world focal point to align the left- and right-side virtual images. At the same time, the user's left and right eyes also undergo accommodation to bring the respective left- and right-side virtual images into focus. However, the distance of the real-world focal point may frequently differ from the distance of the augmented-reality display, causing a difference between the apparent vergence distance and the apparent accommodation distance of a virtual object. Unfortunately, because the human visual system is adapted to the expectation that the apparent vergence distance and the apparent accommodation distance of a real-world object will match, the mismatch frequently posed by traditional augmented reality systems may confuse a user's vision, potentially breaking a sense of immersion—or even causing severe physical discomfort.